Laravel 5 Validation in controller

I have 2 functions in my controller and I need to do validation for it but I don't know how.

1st function which should allow all image extensions:

public function testing(Request $request) {
    if($request->hasFile('img'));
    {
        $image = Input::file('img');
        $filename = time() . '.' . $image->getClientOriginalExtension();
        $path = public_path('images/' . $filename);
        Image::make($image->getRealPath())->resize(200, 200)->save($path);
        $file = $request->file('img');
        return ['url' => url('images/' . $filename)];
    }
}

2st function which should only allow 1 word and if there is space, trim it into 1 word:

    public function postDB(Request $request) {
    $newName = $request->input('newName');
    $websites = new Website();
    $websites->name = $newName;
    $websites->save();
    return redirect('template')->with('status', 'Website has been saved successfully!');
}

via Przemek